Hi,
I've gone to field management > new > and created a new field named Age (which was auto-renamed to cb_age). The type is a text field, under Additional Information Tab, with the title Age.
I've made it required, showing on profile Line 1, and it is displayed on the field title on the profile.
It is marked search-able for users, yes for read online, yes for show at registration, and yes for published.
On the front end of my site, it only displays the search criteria Username